If you are contributing to a personal fundraiser (e.g. someone raising money to cover funeral expenses), your contribution is generally not tax deductible.
Charitable donations made via Obituare to U.S. charities are usually tax-deductible unless an individual collects the funds to donate to a charity. You can see on the fundraiser if this is the case.
If you have questions about the deductibility of a donation, it's a good idea to contact a tax professional.